PROGRAM loops;

  VAR 
    sum, i, n: INTEGER;
    sumReal: REAL;

BEGIN 
  sum := 0;
  i := 1;
  n := 10;

  WHILE i <= n DO BEGIN 
    sum := sum + i;
    i := i + 1;
  END;

  sum := 0;
  i := 1;
  REPEAT 
    sum := sum + i;
    i := i + 1;
  UNTIL i > n;

  sum := 0;
  FOR i := 1 TO n DO BEGIN 
    sum := sum + i;
  END;

  sumReal := n * (n + 1) / 2;

  ReadLn();
END.